Steam hydraulic indensifier



T. W. HAND.

STEAM HYDRAULIC INTENSIFIER.

APPLICATION FILED DEC. 10. I918.

. Patented Feb. 24,1920.

I a SHEETS-SHEET my/ 0.4M q u w T. W. HAND.

SIEAM HYDRAULIC INTENSIFIER. APPLiCATlON FILED 05c. 10. I918.

Patented Feb. 24 1920.

T. W. HAND.

STEAM HYDRAULIC iNTENSIFIER.

APPLICATION FILED DEC. I0. 1918.

3 SHEETS-SHEET 3.

- 1,331,991 Patented Feb. 24,1920.

' UNITED STATES PATENT OFFICE.

THOMAS WILTON HAND, 0F SHEFFIELD, ENGLAND, ASSIGNOR TO DAVY BROTHERS,

' LIMITED, 0F SHEFFIELD, YORK; ENGLAND.

l STEAM HYDRAULIC INTENSIFIER.

Specification of Letters Patent.

Patented Feb. 24, 1920.

Application filed December 10, 1918. Serial No. 266,026.

ain, residing at Sheffield, in the county of York, England, have invented new and useful Improvements in and Connected with Steam Hydraulic Intensifiers, of which the following is a specification.

This invention relates to hydraulic intensifiers worked by elastic motive fluid (hereinafter, for the sake of convenience, referred to as steam), the object of the invention being to provide what may be termed a compound steam hydraulic intensifier, that is to say, an intensifier with two or more steam cylinders adapted to utiliZe the steam expansively in suchmanner that, when the hydraulic forging press,

shears, or other apparatus actuated by the intensifier is required to work under relatively light load or equivalent conditions, the intensifier can be made to operate substantially as a compuond steam engine, whereas, when the press or other apparatus is required to work under conditions of full or relatively heavy load, the intensifier can be made to operate with high steam pres sure in what is normally the low-pressure steam cylinder.

Reference is to be had to the accompanying drawings, wherein Figure 1 is a somewhat diagrammatic side elevation illustrating one form of the invention as applied to a steam hydraulic intensifier having two steam cylinders, the steam and hydraulic cylinders with their supports being all shown in axial section; while Fig. 2 is a view similar to Fig. 1 but showing a modified arrangement of steam connections adapted to enable the maximum pressure to be obtained from the apparatus. Figs. 3 and a show, to a larger scale and partly in section, an automatic steam stop-valve which may be employed as indicated in Fig. 2, the valve being viewed, in Figs. 3 and 4 respectively, in two directions at right angles to one another.

Referring first to Fig. 1, 11 is the hydraulic cylinder, which is mounted at 12 in the lower member of an open frame or stool 13, the axis of the cylinder being arranged vertically and the hydraulic ram 14 being adapted to-perf rm its working stroke 111- the upward direction. A steam cylinder 15 of relatively large diameter, is mounted upon the stool 13 in axial alinement with the hydraulic cylinder 11, the upper mem: ber 16 of the stool constituting the bottom cover of the cylinder 15. A steam cylinder 17 of relatively smalldiameter is mounted above and in axial alinement with the cylinder 15; an open frame or stool 18, which is interposed between the cylinders 15 and 17, having a lower member 19 which constitutes the top cover of the cylinder 15 and an upper member 20 which constitutes the bottom cover of the cylinder 17. Pistons 21 and 22, fitted to reciprocate in the respective steam cylinders 15 and 17, are connected by an axially-extending piston-rod 23 which passes through stuiling boxes 24 and 25 provided respectively in the lower and upper members 19 and 20 of the stool 18. The maximum efi'ective stroke is the same for both steam pistons 21 and 22 and also for the hydraulic ram 14, which is coupled to the lower steam piston 21 so as to move as one with both pistons 21 and 22. For this purpose a cross-head 26 on the lower end of the ram 14 is connected with the piston 21 by a'pair of side rods 27 which extend, at opposite sides-of and parallel with the ram '14.. through guides 28 in the lower member of the. stool 13 and through stufiing-boxes 29 in the bottom cover 16 of the cylinder 15.

In the example illustrated, the steam inlet and exhaust valves of both the steam cylinders are to be understood as doublebeat drop valves 0tusual construction; the steam'inletand-exhaust port 30 of the larger cylinder 15 communicating both with the inlet valve 31 and also with the exhaust valve 32, while the steam inletand exhaust-port 35 of the smaller cylinder 17 communicates both. with the inlet valve 33 and also with the exhaust valve 34. The high-pressure steam supply pipe 36 is on the one hand permanently connected, by a pipe 37, with the inlet valve 33 of the cylinder 17, and on the other hand is connected with the inletvalve 31 of the cylinder 15 by a pipe 38 provided with a stop-valve 39, (which'is shown as an ordinary screw-down valve). The exhaust valve 32 of the cylinder 5 i c nn c d ith the s ain exhaust 15 is connected, by a pipe 44, with the main exhaust pipe 40; and the upper end of the cylinder 17 is closed, and connected, by a pipe 45, with the receiver 42.

All the steam inlet and exhaust valves 31, 32, 33, 34, are controlled concurrently, and in the same sense for the valves of both cylinders 15 and 17, on the one hand manually by means of a single handing-lever, and on the other hand automatically by means of hunting-gear adapted to cause the supply of steam to both cylinders to be cut off, during each working stroke of the intensifier, at a point corresponding to the angular position wherein for the time being the handing-lever is held.

For the purpose of effecting the manual control of the valves, the handing-lever 46, which is tulcrumed at a fixed point 47, has an arm 48 coupled by an upright rod 49 to the longer arm of what may be termed the main lever 50 in each of the respective sets of valve-actuating mechanism appertaining to the steam cylinders 15 and 17. The two sets of valve-actuating mechanism, which are substantially identical in construction, comprise in each case the aforesaid main lever 50, which is substantially horizontal and is fnlcrumed at a fixed point 51 at a level considerably above the valves 31 and 32, or 33 and 34; a floating lever 52 which is connected by one end to the shorter arm of the main lever 50 and by the opposite end to an intermediate point in the upper section of an upright link 71 formed in two sections which are coupled together by a pin-.andslot connection 71, the, lower end ofthe lower section of this link being connected to the spindle 57' of the exhaust valve 32 or 34; and a substantially horizontal rocking lever 53 which is ful claimed at a fixed point 54 beneath the level of. the main lever 50.and floating, lever 52; this rocking lever being coupled at one end to the spindle 55 of the steam inlet valve 31 or 33 by a pin-and-slot connection 56, at'

the opposite end to an intermediate point in the lower section of the link 71 by a pin-and-slot connection 59, and, at a point between; said connection 59 and the fulcrum 54. to an intermediate point inthe floating lever 52 by means of an. upright link 58 The hunting-gear for effecting the automatic control of the valves is actuated by an upright, upwardly-tapering cam-bar 6O fixed at 61 to, and extending upward from, the cross-head 26 and having one edge 62 irc ined'to thedire'tion of motion of the bar while the, oppo i e. edge, which is parallel to said direction, is guided by contact with a stationary roller 63. Against the inclined edge 62 of this cam-bar, bears a roller 64 carried by one limb of a three-armed lever 65 which is fulcrumed at a fixed point 66, contact between the roller and cam-bar being insured by a counterweight 67 suspended from a second limb of the lever 65. A third limb of the same lever is coupled by an upright rod 68 to one arm of what may be termed the secondary lever 69 (as distinguished from the main lever 50) of the valve-actuating mechanism appertaining to each steam cylinder 15 and17;each secondary lever 69, which is fulcrumed at a fixed point 70 above the level of the floating lever 52, having its other arm connected'tothe upper end of the link 71 and thus to that end of the corresponding floating lever 52 which is remote from the main lever 50.

In the drawing all the working parts are 7 shown in their resting positions, the hyhigh-pressure steam to be admitted through the connection 36 to the pipe 37, or (if the stop-valve 39 be open) to both the pipes 37 and 38, the handing-lever 46 is oscillated toward the right or toward the left of its neutral position according as'the intensifier is required to perform a working (2'. e. an upward) stroke or a return (i. e. a downward) stroke consequent on the opening of the steam inlet valves 31 and 33, or of the steam exhaust valves 32 and 34.

Let it now be supposed that the intensifier is required to work under relatively light load or equivalent conditions ;-at starting, the stop valve 39 being closed the first time the handing-lever 46 is moved toward the right 01" its neutral position,

although both the inlet valves 31 and 33 will be opened while the exhaust valves 32 and 34 remain closed, yet the absence of steam between the exhaust valve 34 of the smaller and the inlet valve 31 of the larger steam angular position; wh ch tor: thetime being thehanding-lever is held, the action of the hunting-gear will cause the inlet valves 31 and 33 to close, so that the upward movement will be arrested and the pistons and ram will be supported by the steam beneath the smaller piston 22. If the handing-lever 46 be now'moved toward the left of its neutral position, the inlet valves 31 and 33 will remain closed but the exhaust valves 32 and will be opened, with. the result that the pistons and ram will descend. by gravity; the piston 22 expelling the steam from the cylinder 17 into the receiver 42 by way of the pipe 41, while at the same time equilibrium of pressures above and beneath the respective pistons is insured by the pipes 44 and 45. Next time the handing-lever 46 is moved toward the right of its neutral position, not onlv will the consequent opening of the inlet valve 33 admit high-pressure steam beneath the smaller pis ton 22 as before, but the opening of the in let valve 31 will admit steam from the receiver 42 beneath the larger piston 21 by way of the pipes 43 and 38, with the result that the steam which had previously done duty at high pressure in the smaller cylin der 17 will now act expansivelv in the larger cylinder 15, the piston 21 inwhich will therefor cooperate with the piston 22 in raising the ram 14 and producing hydraulic pressure in the cylinder 11 and pipe '72.

In practice. the hydraulic pressure obtained b using expansively in the larger steam cylinder 15 the steam exhausted from the smaller steam cylinder 17 would preferably be equal to (say) about two-thirds of the load on the press or other hydraulic apparatus when full-pressure steam is admitted to the smaller steam cylinder; lighter loads being met bv throttling" the supply of steam to the smaller cylinder.

If the intensifier be reouired to work under relatively heavy load or equivalent cond tions. the stop-valve 39 is opened so as to allow live steam to gain access to the inlet valve 31 of the larger steam cylinder, with the result that each time the handing lever 46 is moved toward the right of its neutral position high-pressure steam will be admitted not onlv beneath both pi tons 21 and 22 but also above the piston 22 by way of the. pipe 43, receiver 42, and pipe 45; so that while the intensifier will now work under t e increased efiective steam pressure due to the larger area of the lower piston 21', the upper piston 22 will be rendered inoperative owing' to equilibrium of pressures being; established upon its opposite sides. In order to obtain the highest possible pressure, it is necessary, while admitting live steam beneath. both pistons 21 and 22, to

7 receiver 42 must be isolated from the pipes 41, 43, and 45, and the pipes 41 and 45 conshow a device which may be used, if desired, for the purpose of admitting live steam beneath the pistons of both steam cylinders either automatically on the hydraulic pressure reaching the maximum attainable by the use of the apparatus as a compound intensifier, or. at any other time at will.

In Fig. 2, the hydraulic cylinder 11 and ram 14, the steam cylinders 15 and 17 with their inlet and exhaust valves 31, 32 and 33, 34, as well as the handing-lever 46 and the rest of the mechanism for operating said valves, are all as already described and are denoted by the same reference symbols, so that the explanation of the arrangement and operation of these parts need not be repeated.

In Fig. 2, however, the high-pressure steam supply pipe 36, which is on the one hand permanently connected, by a pipe 37, with the inlet valve 33 of the smaller steam cylinder 17 as before, is on the other hand connected with the inlet valve 31 of the larger steam cylinder 15 by a pipe 73 in which is interposed a valve 7 4 (hereinafter described in detail) which is normally closed but which is adapted to open automatically on the hydraulic pressure in the cylinder 11 and hydraulic main pressure pipe 72 reaching the maximum attainable by the use of the apparatus as a compound intensifier as already set forth. The valve 74 is also provided with means whereby it may be opened, and kept open. manually when desired, as for example when the development of the maximum hydraulic pressure is required to con inue during" a considerable period.

The steam receiver 42, which is permanently connected with the upper end of the smaller steam cylinder 17 by a pipe 45 as before, is connected with the pipe 73 (and therefore with the inlet valve 31 of the larger steam cylinder 15) by a pipe 75 which is controlled by a stop-valve 76, which isshown as an ordinary screw-down valve. The exhaust valve 34 of the smaller steam cylinder 17 discharges directly into the receiver 42 by a pipe 41 as before: while a branch 77 from this pipe 41, controlled by a stop-valve 78 (shown as an ordinary screw-down valve) communicates with the main exhaust pipe 40 leading from the exhaust valve 32 of the larger steam cylinder 15. The pipe 44 which. as before, connects the upper end of the cylinder 15 permanently with the main exhaust pipe 40, is shown in Fig. 2 (for the sake of convenience) as leading from said cylinder to a point in the pipe 77 between the main exhaust pipe and the stop-valve 78.

In normal expansivepw rking (i h n r the steam exhausted from the smaller steam cylinder 17 is allowed to pass into and act expansively in the larger steam cylinder 15), the valve 76 is kept open and the valve 78 is kept closed, while the automatic valve 74 does not open. In these circumstances, during each upward stroke of the steam pistons 21 and 22, high-pressure steam gains access from the pipe 36 to the smaller steam cylinder 17 alone, by way of the pipe 37 and the inlet valve 33 of said cylinder, while at the same time the steam which was discharged from the cylinder 17 through its exhaust valve 34 during the preceding downward r stroke of the piston 22, and which had entered the receiver 42 by the pipe 41, passes thence to the inlet valve 31 of the larger steam cylinder 15 by way of the valve 76 and pipes 75 and 73. On the hydraulic pressure developed in the cylinder 11 the hydraulic main pressure pipe 72 reaching the maximum attainable with such expansive working, the valve 74 opens automatically so that now, during each upward stroke of the steam pistons 21 and22, high-pressure steam passes not only into the lower end of the smaller steam cylinder 17, but also into the lower end of the larger steam cylinder 15 by way of the valve 74 and pipe 73. At the same time, however, high-pressure steam gains access to the upper end of the smaller cylinder 17 by way of the pipe 75, valve 76 (which is open), receiver 42, and pipe 45, so that although the intensifier Will now work under the increased effective steam pressure due to the larger area of the lower piston, the upper piston 22 will be rendered inoperative as described with referenceto the operation, in similar circumstances, of the arrangement illustrated in Fig. 1. The higher hydraulic pressure developed as the result of the opening of the'valve 74 may (if desired) be maintained for an indefinite time, or may be brought about at any moment (during normal expansive working when required) by opening the valve 74 manually.

In the event of the maximum possible bydraulic pressure required to be obtained, it is necessary, while admitting high-pressure steam beneath both pistons 21 and 22. to exclude such steam from above the smaller piston 22; for which purpose the valve 74 must be kept open bv hand, the valve 76 closed, and the valve 78 opened.

In these circumstances, during each upward stroke of the steam pistons 21 and 22, high-pressure steam gains access from the pipe 36 both to the lower end of the smaller cylinder 17 by way of the pipe 37 and also to the lower end of the larger cylinder 15 by way of the valve 74 and pipe 73. while during each downward stroke of the pistons, exhaust steam is discharged to the main exhaust pipe 40 not only directly from the larger-cylinder .l5as. before but also from the smaller cylinder 17 by way of the pipe 41, valve 78, and pipe 77. It will be seen that, so long as the valve 76 is closed and the valve78 is open, the upper end-of the cylinder. 17 is cut off fromthe main steam supply pipe 36, but remains constantly in communication with the exhaust pipe 40 by wayof the pipe 45, receiver 42, pipe 41, valve 78, and pipe 77. p I

The construction and operation of the automatic valve, as illustrated in Figs. 3 and 4, are as follows :The casing 74 of the valve has at one end an inlet 79 leading from the high-pressure steam supply pipe 36 into the upper part 80 Oftlle valvechamber, and at the other end an outlet 81 leading from the lower part 82 of the valve-- chamber to the pipe 73 which communicates with the inlet valve 31 of the larger steam cylinder 15; while communication between the upper and lower parts 80 and 82 of the valve-chamber is controlled by the valve proper 84, which is a vertically working, double-beat, unbalanced drop-valve adapted to close in the downward direction, and whereof the upper seating 83 is of larger diameter than the lower seating 85 so that the valve has a constant tendency to close under the steam pressure admitted to the upper part 80 of the valve-chamber. The valve-spindle 86, which extends upward, is connected to a point near the middle of the length of a substantially horizontal lever 87 tulcrumed at 88 and adjustably loaded at its free extremity by means of a weight 89; Near the fulcrum 88, the lever 87 has a pinand-slot connection at 90 with a link 91 whereby it is coupled to the upper end of a small hydraulic ram 92 fitted to work vertically in a stationary hydraulic cylinder 92, the ram 92 being adapted to perform its operative stroke in the upward direction; while the cylinder 93 is inperm'anent communication with the hydraulic main pressure pipe 72 (Fig. 2) by way of a branch pipe 94. Near its freeextremity the lever 87 has a pin-and-slot connection at 95 with the upper end of an upright rod 96 through which the lever can be manually actuated. the lower end of the rod 96 being coupled to an arm 97 fast on the horizontal fulcrum-shaft 98 of a hand-lever 99 which, as indicated in Fig. 2, is arranged in convenient proximity to the main handing-lever 46 wherebv the strokes of the intensifier are controlled.

The constant tendency of the-automatic valve to closeunder steam pressure is assisted by the weight 89 acting through the lever 87; the total force which thus acts downward upon the valve being just suflicient to counteract the upward effort exerted upon the lever 87 by the hydraulic ram 92, so long as the hydraulic pressure in the cylnd r, 3 is Slightly l w the max m limit attainable by the use of the apparatus as a compound intensifier. Upon the hydraulic pressure in the cylinder 11 of the intensifier (and therefore also in the pipes 72 and 94 and in the cylinder 93) reaching the maximum limit attainable by the use of the apparatus as a compound intensifier, the hydraulic pressure in the cylinder 93 becomes suflicient to enable the upward effort of the ram 92 upon the lever 87 to overcome the combined downward effort of the weight 98. and of the steam pressure tending to close the automatic valve, with the result that this valve now opens and permits high-pressure steam to gain access to the larger steam cylinder 15. The pinand-slot connection at 9:") permits of .the automatic upward movement of the lever 87 being performed without affecting the rod 96 and hand-lever 99. a

If, while the intensifier is working expansively, it is desired to admit high-pressure steam to the larger steamcylinder 15, this may be effected manually by so operating the hand-lever 99 as to raise the lever 87 and open the automatic valve against the combineddownward efiort of the weight 89 and of the steam pressure tending to close the valve; the pin-and-slotconnection at 90 permitting of the upward movement of the lever 87 being performedwithout affooting the hydraulic ram 92.

In the same way the, automatic valve, ai'ter being opened by hydraulic pressure on the maximum limit of such pressure being reached during normal expansive working,

may be kept open for an indefinite period by the use of the hand-lever 99.

It will be obvious that any convenient means may be provided for enabling the stop-valves 76 and 78 (Fig. 2) to be manu-- ally controlled from a point in convenient proximity to the hand-levers -16 and 99, if desired. These stop-valves might also be controlled through the medium of a power.

relay.

Inasmuch as the receiver 42 constitutes, 1n eilect, merely a local enlargementof the pipes with which it is immediately connected, it will be obvious that the provision or" a structurally distinct receiver (such for example as that shown at e2 in the drawing) is not essential, andthat the pipes which are shown as connected together'through the medium of the re'eiver might, if, of sufficient capacity, he made continuous with one another asa single pipe, the pipe 45 being joined to the remainder of the pipe-system at a suitable branch.

In the foregoing description, the elastic motive fluid operating in the intensifier is for the sake of convenience referred to as steam, but it will be evident that other elastic motive fluid (such as compressed air.

for example) m'ayfbe used; and hence it is to be understood that both throughout the description and in the appended claimsthe term steam is to be interpreted as including any kind of elastic motive fluid.

I claim 1. In a hydraulic intensifier operated by elastic motive fluid, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a ram cooperating therewith, of a plurality of cylinders located in cooperative relation, pistons in said cylinders coupled to one another and to the movable member of said pair of hydraulic elements whereby said pistons and movable member are concurrently operated, means controlling the admission of motive fluid at the maximum pressure to one of said cylinders a connection leadin from the rear or inlet end of said cylinder to the rear of another of said cylinders, means controlling the discharge of the motive fluid exhausted from the rear of said first named cylinder to the rear of said other cylinder and mechanism for actuating all of said controlling means in'coordination with one another.

In a hydraulic intensifier operated by elastic motive fluid, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith, of a plurality of elastic fluid cylinders of progressively increasing diameters, pistons fitted to reciprocate in the respective elastic fluid cylinders and coupled to one another and to the movable member of said pair of hydraulic elements, whereby said pistons and movable member are concurrently operated, passages and valves thereon for admitting elastic motive fluid at the maximum working pressure to the cylinder of least diameter, for leading the motive fluid exhausted from each cylinder of lesser diameter to each cylinder of next larger diameter, and for discharging the motive fluid exhausted from the cylinder of largest diameter respectively, and mechanism for actuating all of said valves in coordination with one another.

3. In a hydraulic intensifieroperated by elastic motive fluid, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith, of a. plurality of elastic fluid cylinders of" progressively increasing diameters, pistons fitted to reciprocate in the respective fluid cylinders and coupledto one another and to the movable member of said pair of hydraulic elements, passages for actuating all of said valves in coiirdination with one another, and a receiver for elastic motive fluid interposed, in each passage connecting two cylinders, between the exhaust valve of the smaller and the inlet valve of the larger cylinder.

4. In a hydraulic intensifier operated by elastic motive fluid, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith, of a plurality of elastic fluid cylinders of progressively increasing diameters, pistons fitted to reciprocate in the respective elastic fluid cylinders and coupled to one another and tothe movable member of said pair of hydraulic elements, whereby said pistons and movable member are concurrently operated, passages and valves thereon for admitting elastic motive fluid at the maximum working pressure to each motive fluid cylinder, for leading the motive fluid exhausted from each cylinderof lesser diameter to each cylinder of next larger diameter, and for discharging the motive fluid exhausted from the cylinder of largest diameter respe'tively and mechanism for actuating a plurality of said valves in coordination with one another. 1

5. In a steam hydraulic intensifier, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith, the members of said pair having their common axis arranged vertically and the one mem her being stationary While the other is adapted to perform its working stroke in the upward direction, of steam cylinders of relatively large and relatively small diam eter mounted in axial alinement with one another and with the members of the pair of hydraulic elements, single-acting pistons fitted to recipro'at'e in the respective steam cylinders, an axially-extending piston-rod attached to both of said pistons, a crosshead on the movable member of the pair of hydraulic elements, rods attached eccentrically to one of the steam pistons and to said crosshead and extending parallel to the cylinder axis, whereby said movable member and said pistonsrare concurrently actuated, pas

sages and valves thereon for admitting high-pressure steam to the lower end of the smaller steam cylinder, for leading the steam exhausted from the lower end of said cylinder to the lower end of the larger steam cylinder, and for discharging the steam exhausted from the lower end of the last-mentioned cylinder respectively, and mechanism for actuating all of said valves in. coordination with one another.

6; In a steam hydraulic intensifier, the.

combination with apair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to coonerate therewith. the, members of said pair having their common axis arranged vertically and thepne memher being stationary while the other is adapted to perform its working stroke in the upward direction, of steam cylinders of relatively large and relatively small diameter mounted in axial alinement with one another and with the members of the pair of hydraulic elements, single-acting pistons fitted to reciprocate in the respective steam cylinders, an axially-extending piston-rod attached'to both of said'pistons,'a crosshead on the movable member of the pair of hydraulic elements, rods attached eccentri ally to one of the steam pistons andto said crosshead and extending parallel to the cylinder axis, passages and valves thereon for admitting high-pressure steam to the lower end of the smaller steam cylinder, for leading the steam exhausted from the lower end of said cylinder tothe lower end of the larger steam cylinder, and for dis harging the steam exhausted from the lower end of the last-mentioned cylinder respectively, mechanism for actuating all of said valves in coordination with one another, and a steam re eiver interposed in the passage mounted in axial alinement with one another and with the membersof the pair of hydraulic elements, single-acting pistons fitted to reciprocate in the respective steam cylinders, an axially-extending piston-rod I attached to both of said pistons, a crosshead on the movable member of the pair of hydraulic element's, rods'attached eccentrically to one of the steam pistons and to said crosshead and extending parallel to the cylinder axis, whereby said movable member and said pistons are concurrently actuated, passages and valves thereon for admitting high pressure steam to the lower end of the smaller steam cylinder, for leading the steam exhausted from the lower end of said cylinder to the lower end ofithe larger steam cylinder, and for dis harging the steam exhausted from the lower end of the last mentioned cylinder respectively, mechanism for actuating all of said valves in coordination with one another, a passage for admitting high-pressure stean'ito the lower end of the larger steam cylinder, and a stop-valve on said passage.

8. In a steam hydraulic intensifier, the

head and extending parallel to the cylinder combination with a pair of hydraulic elements comprising a hydraulic cylinder and a rain adapted to cooperate therewith, the members of said pair having their common axis arranged Vertically and the one member being stationary while the other is adapted to perform its working stroke in the up ward dir ction, of steam cylinders of relatively large and relatively small diameter mounted in axial alinement with one another and with the members of the pair of hydraulic elements, single-acting pistons fitted to reciprocate in the respective steam cylinders, an axially-extending piston rod attached to both of: said pistons, a crosshead on the movable member of the pair of hydraulic elements, rods attached eccentrically to one of the steam pistons and to said crossaxis, passages and valves thereon for admitting high-pressure steam to the lower end of the smaller steam cylinder, for leading the steam exhausted from the lower end of said cylinder to the lower end of the larger steam cylinder, and for discharging the steam exhausted from the lower end of the last mentioned cylinder respectively,

mechanism for actuating all'of said valvesin coordination with one another, and passages for affording open communication between the upper ends of the respective steam cylinders, and the exhaust passages from the lower end of said cylinders at points beyond the respective exhaust valves.

9. In a steam hydraulic intensifier, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith, the members of said pair having their common axis arranged vertically and the one memher being stationary while the other is adapt ed to perform its working stroke in the upward direction, of steam cylinders of relatively large and relatively small diameter mounted in axial. alinement with one another and with the members of the pair of hydraulic elements, single-acting pistons fitted to reciprocate in the respective steam cylinders, axially ext-ending piston-rod attached to both of said pistons, a crosshead on the movable member of the pair of hydraulic elements, rods attached eccentrically to one of the steam pistons and to said cross head and extending parallel to the cylinder axis, passages and valves thereon for admitting higlrpressure steam to the lower end of the smaller steam. cylinder, for leading the steam exhausted from the lower end of said cylinder to the lower end of the larger steam cylinder, and for discharging the steam exhausted from the lower end of the last mentioned cylinder respectively, a single handing-l'ever and mechanism connected therewith for controlling all of said valves, and automatically-acting hunting-gear actuated by themovement of the steam pistons and adapted to cooperate with said handing-la tor and connected mechanism, for causing the supply of steam to both steam cylinders to be cut oil during each working stroke of the intensifier at a point corresponding to th'e angular position wherein for the time being the handing-lever is held.

10. In a steam hydraulic intensifier, the combination of a stationary hydraulic cylinder having its axis arranged vertically, a ram fitted to reciprocate in said cylinder and adapted to perform its working stroke in the upward direction, a steam cylinder of relatively large diameter mounted above and in axial alinement with the hydraulic cylinder, a steam cylinder of relatively small diameter mounted above and in axial. alinement with the larger steam cylinder, single-acting pistons fitted to reciprocate in the respective steam cylinders, an axially-extending piston-rod attached to both of said pistons, a crosshead on the hydraulic ram, rods attached eccentrically to the largersteam piston and to said crosshead and extending par allel to the cylinder axis, passages and valves thereon for admitting higlrpressure steam to the lower end of the smaller steam cylinder, for leading the steam exhausted from the lower end of said cylinder to the lower end of the larger steam cylinder, and for discharging the steam exhausted from the lower end of the last mentioned cylinder respec tively, a sin gle handing-lever and mechanism connected therewith for controlling all. of saic valves, an upright cam-bar attached to said crosshead and having one edge inclined to the direction of movement of the bar, and a lever adapted to bear against said inclined edge and coupled to the handinglever through said connected mechanism, for causing the supply of steam to both steam cvlinders to be cut of]? during each working stroke of the intensifier at a point corresponding to the angular position wherein for the time being the handing-lever is held.

11. In a hydraulic intensifier operated by elastic motive fluid, the combination of a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith; a pair of elastic fluid cylinders of relatively large and relatively small diameter respectively; individual pistons fitted to reciprocate in the respective elastic fluid cylinders, a connection whereby said pistons are coupled to one another and means connecting said pistons to the movable member of said pair of hydraulic elements for causing said member to move as one with the pistons; passages and valves thereon severally for admitting elastic motive fluid at the maximum working pressure to the cylinder of smaller diameter, for

leading the motive fluid discharged from said cylinder to the cylinder of larger diameter and, alternatively, to exhaust, for admitting elastic motive fluid at the maximum working pressure to the cylinder of larger diameter, for leading the motive fluid discharged from "said cylinder to exhaust, and mechanism for actuating all of said valves in coordination with one another.

12. In a hydraulic intensifier operated by elastic motive fluid, the combination of a pair of hydraulic elements comprising a hydraulic cylinder and a ram adapted to cooperate therewith; a pair of elastic fluid cylinders of relatively large and relatively small diameter respectively; pistons fitted to reciprocate in the respective elastic fluid cylinders and coupled to one another and to the movable member of said pair of hydraulic elements for causing said member to move as one with the pistons; passages and valves thereon severally for admitting elastic motive fluid at the maximum workingpressure to the cylinder of smaller diameter, for leading the motive fluid discharged from said cylinder to thecylinder of larger diameter and, alternatively, to exhaust, for

admitting elastic motive fluid at the maxi- V mum working pressure to the cylinder of larger diameter, for leading the motive fluid discharged from said cylinder to exhaust, mechanism for actuating'all of said valves in coordination with one another, and means for causing the admission of elastic motive fluid at the maximum working pressure to the cylinder of larger diameter to take place automatically on the pressure in the hydraulic cylinder exceeding a predetermined limit.

13. In a hydraulic intensifier operated by elastic motive fluid, the combination with a pair of hydraulic elements comprising a hydraulic cylinder and a rain cooperating therewith, of a plurality of cylinders, pis

tons reciprocating in said cylinders and con nected with each other, means whereby the movable member of said pair of hydraulic elements is connected with said pistons, connections for conducting motive fluid to said cylinders, a normally closed valve in at least one of said connections whereby the admission of motive fluid to the connected cylinder-is controlled and means whereby sion of motive fluid to the connected 'cyling der is controlled, means whereby said valve is automatically opened when the hydraulic pressure reaches the maximum and inanually operated means whereby said valve may be actuated independently of itsautomatic actuation.

15. In a hydraulic intensifier operated by elastic motive fluid, the combination with a pair of hydraulic elements comprising a-hydraulic cylinder and a ram cooperating therewith, of a plurality of cylinders located in cooperative relation, pistons in said cylinders coupled to one another and to the movable member of said pair of hydraulic elements whereby said pistons. and movable member are concurrently operated, a conduit leading "from the exhaust end of one of said cylinders to the inlet end of another of said cylinders, an exhaust pipe connected pipe connected therewith, a valve in said line for controlling the passage of said motive fluid and another valve also in said line for opening the exhaust pipe on the return stroke of the piston in said cylinder and mechanismfor actuating all of said valves in coordination with one another.

THOMAS WILTON HAND. 

